A convoy can be used to transport large quantities of items to a certain destination in order to reduce the amount of time and number of return trips required, provide support for vehicles in order to attain safe travel, and can also be used to reduce traffic congestion on roadways. A robotic convoy can be used to further the efficiency of convoy missions in many different areas.
The robotic convoy concept can be used with many different types of robotic vehicles. In its simplest form, the robotic convoy includes a leader vehicle and a follower vehicle. The leader and follower vehicles can be in two-way communication throughout a mission. It is then possible for the follower vehicle to receive information from the leader vehicle in order to aid the follower vehicle in following the path of the leader vehicle.
In the past, different methods for following the leader vehicle have been developed. One such method uses the global positioning system (GPS) to provide position information for the various vehicles. Unfortunately, however, GPS receives require a direct view or “line-of-sight” access to at least three, and typically more, GPS satellites. This direct view or line-of-sight limitation typically prevents GPS systems from being used around large buildings (e.g., in urban areas), in tunnels, or underground. Furthermore, the position update frequency of most GPS systems is not rapid enough to allow for fast traveling where the convoy vehicles are close and rapid response times are required.
Another type of convoy system uses magnetic markers wherein permanent, discrete magnetic markers line the path to be driven. This system has limited utility in that it can only be used where magnet markers are present. Camera-based robotic convoy systems have also been developed in which the follower vehicle uses one or more cameras to track the leader vehicle. However, the data received from the camera is too large and cumbersome for use at high speeds. Another drawback is that the leader vehicle must always be in the line of sight of the camera.